Chronopotentiometric methods were used to study the diffusion of Zr ions which were in equilibrium with metallic Zr in the alkali chloride melt. The results for temperatures of between 690 and 940C could be described by:
D (cm2/s) = 1.44 x 10-2 exp[-12.80(kcal/mol)/RT]
It was found that the Stokes-Einstein relationship was of little use in understanding the diffusion behavior of the Zr ions. The data confirmed that the Zr ions which were in equilibrium with metallic Zr in the alkali metal chloride were in the bivalent state.
Diffusion and Valence State of Zr Ions in Equilibrium with Metal in a Medium of Fused Alkali Metal Chlorides. V.E.Komarov, M.V.Smirnov, N.P.Borodina, V.N.Alekseev: Tr. Inst. Elektrokhim., Akad. Nauk SSSR, Ural. Fil., 1969, 13, 3-8